Keeper Ines brings the crew three charts that members made for the hallway board.
"Members are excited about the survey," she says. "But something feels off about these."
Comet points at the first one, a pie chart of the Saturday door count. "Ten slices, one for each hour. Colorful!"
Wren studies all three. "What do you notice? One is the wrong kind of chart. One is missing parts. One has a strange axis."
Nova projects a checklist beside the board. "Would you like a hint?" she asks.
"For each chart, ask what job it is trying to do, and whether it has every part an honest graph needs."
Comet grabs a marker. "Let's check them one at a time."
| Chart | What it shows | What the crew sees |
|---|---|---|
| Chart A | A pie chart of the Saturday door count, one slice for each hour from 10 am to 7 pm | You cannot see the count rise toward 5 pm and fall after it |
| Chart B | A bar graph of Q2: morning 8, afternoon 10, evening 15, weekend 7 | No title and no source line |
| Chart C | A bar graph of Q1: 9, 17 and 14 members | The y-axis labels go 0, 5, 10, 12, 14, 16, 18, evenly spaced |
These charts are made up for the Commons Count story.
Pie charts compare parts of a whole. They do not show changes over time.
A title gives a short explanation of what is in a graph.
A source line explains where the data came from and gives credit to those who collected it.
On a bar graph the y-axis is divided into equal parts.
| Statement | True or false? |
|---|---|
| A pie chart is a good way to show how the door count changed each hour. | ? |
| A graph without a source line does not give credit to those who collected the data. | ? |
| The steps on a bar graph's y-axis should be equal. | ? |
| A chart with every part in place can still be the wrong kind of chart. | ? |
Good eyes, data analyst. Tomorrow in Count Lab you will redraw two misleading charts honestly.